An insight into the hepatocellular death induced by amphetamines, individually and in combination: the involvement of necrosis and apoptosis

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Diana Dias da Silva (Author) Other; Helena Carmo (Author) FFUP; Adam Lynch (Author) Other; Elisabete Silva (Author) Other

Journal

Title: Archives of Toxicology

Vol. 87

Pages: 2165-2185

ISSN: 0340-5761

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 34 Citations

Scopus - 45 Citations

Pubmed / Medline

Scientific classification

FOS: Medical and Health sciences > Basic medicine

CORDIS: Health sciences > Pharmacological sciences > Toicology

Other information

Authenticus ID: P-006-JE4

DOI: 10.1007/s00204-013-1082-9

Abstract (EN): The liver is a vulnerable target for amphetamine toxicity, but the mechanisms involved in the drug's hepatotoxicity remain poorly understood. The purpose of the current research was to characterize the mode of death elicited by four amphetamines and to evaluate whether their combination triggered similar mechanisms in immortalized human HepG2 cells. The obtained data revealed a time- and temperature-dependent mortality of HepG2 cells exposed to 3,4-methylenedioxymethamphetamine (MDMA, ecstasy; 1.3 mM), methamphetamine (3 mM), 4-methylthioamphetamine (0.5 mM) and d-amphetamine (1.7 mM), alone or combined (1.6 mM mixture). At physiological temperature (37 A degrees C), 24-h exposures caused HepG2 death preferentially by apoptosis, while a rise to 40.5 A degrees C favoured necrosis. ATP levels remained unaltered when the drugs where tested at normothermia, but incubation at 40.5 A degrees C provoked marked ATP depletion for all treatments. Further investigations on the apoptotic mechanisms triggered by the drugs (alone or combined) showed a decline in BCL-2 and BCL- (XL) mRNA levels, with concurrent upregulation of BAX, BIM, PUMA and BID genes. Elevation of Bax, cleaved Bid, Puma, Bak and Bim protein levels was also seen. To the best of our knowledge, Puma, Bim and Bak have never been linked with the toxicity induced by amphetamines. Time-dependent caspase-3/-7 activation, but not mitochondrial membrane potential (a dagger psi(m)) disruption, also mediated amphetamine-induced apoptosis. The cell dismantling was confirmed by poly(ADP-ribose)polymerase proteolysis. Overall, for all evaluated parameters, no relevant differences were detected between individual amphetamines and the mixture (all tested at equieffective cytotoxic concentrations), suggesting that the mode of action of the amphetamines in combination does not deviate from the mode of action of the drugs individually, when eliciting HepG2 cell death.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 21